Brain Stimulation for Parkinson's Works Well With Drugs

Nov. 27, 2001 -- Brain stimulation for Parkinson's disease continues to gain ground. A new study shows that it can reduce some of the problems people experience after taking drugs for a long time.

In people with Parkinson's, levels of the brain chemical dopamine are too low. But, levodopa -- one of the first drugs used to treat Parkinson's symptoms -- increases the amount of dopamine.

However, one of the problems in treating this progressive brain disease is that after years of use, levodopa often doesn't work so well. The effects tend to wear off and uncontrolled muscle movements return, which are very difficult to treat.

Some people have reported that deep-brain stimulation eased some of these uncontrolled movements. So, lead author J.G. Nutt, MD, and colleagues wanted to put this to the test.

Doctors know that stimulating areas of the brain known to be abnormal in Parkinson's disease can improve some of the tremors associated with this brain disease. And a recent study even showed that the characteristic slow movements also improve with brain stimulation.

Deep-brain stimulation involves surgery, where electrodes are implanted deep within specific areas of the brain and are connected to a generator that is placed under the skin and just under the collarbone.

The researchers in this current study looked at 12 people with Parkinson's disease who had deep brain stimulators implanted. All of these people were also experiencing a wearing-off effect of their levodopa.

The researchers turned the stimulators on one day and off the next to determine their effect.

When the stimulators were on, the participants in the study were able to walk faster and tap their finger faster. These are two indicators that the movement problems improved when the brain was being stimulated.

The researchers say that the brain stimulator is able to reduce the wearing-off effects of levodopa.

Deep-brain stimulation is not meant to replace levodopa, the researchers say. In fact, many people who have an excellent response to stimulation continue to take the drug.

People with Parkinson's often struggle with a depressed mood, and levodopa helps to improve this. So, while deep-brain stimulation can improve movements along with the levodopa, the drug is also helpful in lifting the depression.